Electrochemical Reduction Process of Sb(III) on Au Electrode Investigated by CV and EIS

Abstract

The electrochemical reduction processes of Sb(III) on Au electrode were studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) electrochemical measurements. The CV analyses reveal that the electrochemical reduction of SbnormalO+ on Au electrode includes three parts: the irreversible reduction of adsorbed SbnormalO+ , the reversible underpotential deposition (UPD) of dissociative SbnormalO+ , and the irreversible overpotential deposition of dissociative SbnormalO+ . Combining the analyses about the redox behaviors of SbnormalO+ as well as the CV measuring results, the reduction of Sb(III) to Sb0 in the presence of the complex reagent (tartaric acid normalC4normalH4normalO62− ) can be conjectured as comprised of four processes: the reduction of adsorbed SbnormalO+ to Sb0 , the UPD of dissociative SbnormalO+ , the reduction of absorbed [Sb2(normalC4normalH4normalO6)]2+ to Sb0 , and the reduction of dissociative [Sb2(normalC4normalH4normalO6)]2+ to Sb0 . What can also be conjectured by further EIS studies is that the three electrons are not gained simultaneously during the formation of Sb0 in these four processes.

Electrodeposition of Ni and Te‐doped Cobalt Triantimonide in Citrate Solutions

“…These findings are consistent with literature data for hydrogen evolution from simple acidic solutions on different substrates such as Au, Co, Ni, Sb and Te [31]. The current density for hydrogen evolution on each substrate is related to the binding energy between the substrate and hydrogen atoms [32].…”

“…Recently, the reduction of Sb (III) in tartaric acid solution was studied by Li [32] who found that the vast majority of the deposit came from the reduction of Sb (III) complex. Similarly, since almost all Te (IV) is in a complex form, the limiting current for Te is bound to the diffusion of Te (IV) complex in the electrolyte to the cathode.…”

Electrochemical deposition of Co–Sb thin films on nanostructured gold

“…is so strong that the Au surface is covered with a partially filled monolayer of SbO ? as soon as the electrode is immersed in electrolyte [14,25]. Scanning electron microscopy (SEM) has also identified the formation of a compound at the Au-Sb interface involving at least two top layers of the Au surface [8], which proves furthermore the existence of strong interactions in the Au-Sb system.…”

“…Scanning electron microscopy (SEM) has also identified the formation of a compound at the Au-Sb interface involving at least two top layers of the Au surface [8], which proves furthermore the existence of strong interactions in the Au-Sb system. Therefore, the interpretation of the CV is complicated by other processes that precede or occur simultaneously with Sb thin film [8,14,25]. Although peak D 1 can be seen at all sweep rates, it is more easily detected at higher sweep rates.…”

“…These characteristics make the electrochemical deposition the method of choice for large scale production of many advanced nanostructured materials at low cost. Although the electrodeposition of cobalt on gold [13] and the electrodeposition of antimony on gold [14] have been subjects of many studies in the past, very few papers report on electrochemical deposition of CoSb 3 .…”